package com.itheima.filter;

import com.alibaba.fastjson.JSONObject;
import com.itheima.pojo.Result;
import com.itheima.utils.JwtUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.StringUtils;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Slf4j
//@WebFilter("/*")
public class LoginCheckFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取URL
        String url = request.getRequestURI().toString();
        log.info("请求的url:{}",url);

        //2、判断是否是登录页面
        if (url.contains("login")){
            log.info("登录操作，放行....");
            filterChain.doFilter(servletRequest, servletResponse);
            return;
        }

        //3、获取jwt令牌
        String jwt = request.getHeader("token");

        //4、判断令牌是否有长度
        if (!StringUtils.hasLength(jwt)){
            log.info("token为空，返回未登录信息");
            Result error = Result.error("NOT_LOGIN");
            String notLogin = JSONObject.toJSONString(error);
            response.getWriter().write(notLogin);
            return;
        }

        //5、假如令牌存在
        try {
            JwtUtils.parseJWT(jwt);
        } catch (Exception e) {
            e.printStackTrace();
            log.info("jwt错误，解析失败，返回未登录信息");
            Result error = Result.error("NOT_LOGIN");
            String notLogin = JSONObject.toJSONString(error);
            servletResponse.getWriter().write(notLogin);
            return;
        }

        //6、放行
        log.info("登录令牌正确");
        filterChain.doFilter(servletRequest, servletResponse);
    }
}
